The present invention relates generally to sealing hydraulic fittings in their mating parts and more particularly to sealing those fittings which are sealed by means of O-rings.
In the past, elastomeric O-rings used to seal fittings subjected to cyclic hydraulic pressure fluctuations often failed because of installation damage, loss of elastomer due to abrasion or high pressure extrusion nibbling, or loss of sealing force due to high temperature compression set of the elastomer.
Further, under some conditions, fretting corrosion occurred at the interface between the fitting head and its mating surface which caused loss of torque and loosening of the fitting.